Thanks for your fast reply! After reading your message it ocurred to me that this started after I turned on the IIS performance counters. Previous to that I had only:

IO Read bytes per second
IO Write bytes per second
Processor % Processor time

The issue began when I turned on all of the IIS counters. Removing these counters I do not get the error, though I can reproduce it reliably by adding them back. I have not tried to isolate which counter or which combination of counters is the root cause.

Is it not advisable to use multiple types of counters at the same time or is there documentation outlining recommendations of which counters can safely be used in conjunction with one another?

Thanks again for the reply. For the time being I will stick with the basic IO and processor time counters.